spammysammich wroteCould be, we might be able to find out now as they've just posted a new video a few hours ago! See here -My guess would be a dropped valve due to valve spring failure like I’ve seen on a Subaru.
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Assimilator1 wroteHe’s a VAG fan through and through, you won’t catch him saying much nice about BMW despite VAG cars having their own awful issues. But I’m eager to hear what an engine builder thinks about the issues with these engines.Could be, we might be able to find out now as they've just posted a new video a few hours ago! See here -
Just seen it, he now mentions it'd been remapped and earlier on had lambda codes, although they should've been sorted with the new sensors fitted.
I still think it odd that either a weak mixture or detonation, or both could break the piston up rather than melt it. But it is what it is.
I still think it odd that either a weak mixture or detonation, or both could break the piston up rather than melt it. But it is what it is.
Assimilator1 wroteYeah they might have buried the lead by not mentioning a possible shit tune to begin with. If somebody turned off the knock sensing or leaned out the tune that’s a whole new kettle of fish. But notice that the #8 cylinders rod is S shaped. That’s a pretty classic sign of hydrolocked piston or FOD so maybe there was a lot of compounding elements? For sure there was a fueling issue.Just seen it, he now mentions it'd been remapped and earlier on had lambda codes, although they should've been sorted with the new sensors fitted.
I still think it odd that either a weak mixture or detonation, or both could break the piston up rather than melt it. But it is what it is.
I didn't notice no 8 rod was bent! Blimey!
FOD?
FOD?
With fod bad enough to do that you would think the head and valves would be smashed up pretty bad. But only the one valve head seems to be missing and there is perhaps less damage in the combustion chamber than you would think for something bouncing around in there. I’m no expert though.
spammysammich wroteYea, but 2nd goWith fod bad enough to do that you would think the head and valves would be smashed up pretty bad. But only the one valve head seems to be missing and there is perhaps less damage in the combustion chamber than you would think for something bouncing around in there. I’m no expert though.
, what's FOD?
Foreign Object Damage.
Looks like another engine's been taken out by a bad injector, I'll add it to the list when more info is added. Post here - https://www.m3post.com/forums/showpost.php?p=32126430&postcount=73
(You've already posted there spammysam). - case added.
(You've already posted there spammysam). - case added.
Added 2 new cases from the same car! (JakeLMBE92), 1 mains failure, and the other injectors failure.
Hmm, what happened with that previous case..... [edit] no further updates.
Hmm, what happened with that previous case..... [edit] no further updates.
Great job Assimilator1!!
It will be interesting if the rod bearings being changed will make a considerable difference, and maybe even which bearings.
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It will be interesting if the rod bearings being changed will make a considerable difference, and maybe even which bearings.
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aus wroteThanksGreat job Assimilator1!!
It will be interesting if the rod bearings being changed will make a considerable difference, and maybe even which bearings.
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And good to see you about!
Assimilator1 wroteAdded 2 new cases from the same car! (JakeLMBE92), 1 mains failure, and the other injectors failure.
Hmm, what happened with that previous case..... [edit] no further updates.
Assimilator1M3Dreaming for the list
=> https://www.m3post.com/forums/showthread.php?t=2207935
///M Power-Belgium wroteCheers mate for the heads up.
Will add him to the list when we have more info, atm theirs confusion as to whether it's RBs (see his stroker thread) or mains.
Added Samuel R's case from the UK M3 FB owners group to the 'other' list. Seems a couple of rod bolts went loose at some point after a rod bearing job! 
Their are a few outstanding cases still in the m3cutters blown engine's list, awaiting further info, but what we know so far :-
Oleg from M3 FB owners group - "car starts and drives. Just makes noise above like 2k RPM, also has bunch of metal shavings in the oil filter. No leaks anywhere." (this reply and others seems to be only randomly visible!).
So it sounds like the rod bearings may have spun. I've just asked him if he's had his old engine stripped to see if we can get a solid answer.... he's just replied, not been stripped yet, but plans to.
119k miles on car, "reconditioned motor from 2017 with roughly 75k miles on it and bearings done".
Chris S. - 2011, (has stop/start), 110k miles, rod bearings done at 90k miles.Engine was losing a large amount of oil during trip when failure occurred "topping up 1L every hour or so". So it's possible too much oil was lost and pressure dropped too low? Although there would be low oil level warnings, so it shouldn't have dropped too low..... Posted a video of it running, sounds rough. Awaiting info for engine strip.
Joshua L - Literally no info about this, aside from engine's "popped it's clogs"
Just found other cases on the UK M3 FB group.
Sam G and Aidan Nix M mentioned mains failures in Chris S's post, with Aidan showing a photo of the cracked block.
Aidan's replied already, 2011 car, 112k miles, was knocking loudly (paraphrasing 'cos forums will probably block his word, lol). Sold as broken.
Also from Chris S's post, Duncan G mentioned an injector failure causing a bore score and hydro locked (found post from 2021, car had done 82k), then 18 mths later a rod snapped on the rebuilt engine! (which going by MoT history was somewhere between 93.5 to 111k miles).
And Martin P, injector failure, needs a rebuild!
Anyway, considering the compression loss that engine's suffered, and the symptoms described, it's fair to say that engine is toast really, I've added it to the 'others' list and injector failure.
Their are a few outstanding cases still in the m3cutters blown engine's list, awaiting further info, but what we know so far :-
Oleg from M3 FB owners group - "car starts and drives. Just makes noise above like 2k RPM, also has bunch of metal shavings in the oil filter. No leaks anywhere." (this reply and others seems to be only randomly visible!).
So it sounds like the rod bearings may have spun. I've just asked him if he's had his old engine stripped to see if we can get a solid answer.... he's just replied, not been stripped yet, but plans to.
119k miles on car, "reconditioned motor from 2017 with roughly 75k miles on it and bearings done".
Chris S. - 2011, (has stop/start), 110k miles, rod bearings done at 90k miles.Engine was losing a large amount of oil during trip when failure occurred "topping up 1L every hour or so". So it's possible too much oil was lost and pressure dropped too low? Although there would be low oil level warnings, so it shouldn't have dropped too low..... Posted a video of it running, sounds rough. Awaiting info for engine strip.
Joshua L - Literally no info about this, aside from engine's "popped it's clogs"
Just found other cases on the UK M3 FB group.
Sam G and Aidan Nix M mentioned mains failures in Chris S's post, with Aidan showing a photo of the cracked block.
Aidan's replied already, 2011 car, 112k miles, was knocking loudly (paraphrasing 'cos forums will probably block his word, lol). Sold as broken.
Also from Chris S's post, Duncan G mentioned an injector failure causing a bore score and hydro locked (found post from 2021, car had done 82k), then 18 mths later a rod snapped on the rebuilt engine! (which going by MoT history was somewhere between 93.5 to 111k miles).
And Martin P, injector failure, needs a rebuild!
Assimilator1 wroteStill no more info been added, and seeing as they haven't posted since that one post we're not likely to get anything more.Looks like another engine's been taken out by a bad injector, I'll add it to the list when more info is added. Post here - https://www.m3post.com/forums/showpost.php?p=32126430&postcount=73.
Anyway, considering the compression loss that engine's suffered, and the symptoms described, it's fair to say that engine is toast really, I've added it to the 'others' list and injector failure.
Added a mains failure, Aidan Nix M from UKM3 FB group.
2 injector failure cases by Martin P & Duncan G from the same group, both suffering bore washed & scored.
Btw, this isn't a sudden burst of cases, some of these go back 4-5 yrs, I've just recently become aware of them, some reported to me by Lukeyboi89 from the m3cutters forum who is also a member of the UK M3V8 FB group. Some other cases are other posters in those cases sighting their failures.
2 injector failure cases by Martin P & Duncan G from the same group, both suffering bore washed & scored.
Btw, this isn't a sudden burst of cases, some of these go back 4-5 yrs, I've just recently become aware of them, some reported to me by Lukeyboi89 from the m3cutters forum who is also a member of the UK M3V8 FB group. Some other cases are other posters in those cases sighting their failures.
Assimilator1 Do you have any data on main bearing failure AFTER replacing the rod bearings with either stock or higher clearance?
GeorgeH wroteI don't have a separate list for mains failing after RBs being changed, but I do note if the RBs were changed beforehand, I think I started to do that a few years ago.
So you could do a word search (ctrl+F) within the mains failed lists to find the cases noted that had RBs done beforehand.
Off the top of my head I know these cases are very rare, I would say mid single digits.
Btw re Chris S's cases, something I haven't mentioned here yet (will edit my previous post in a sec), is that he had a major engine oil leak, topping up 1ltr/hr!
God! I've found about 10 cases of injector failures from the past 4-5 yrs at the UK M3V8 & E9X M3 V8 FB group this week!
Will add them soon.
In part to this (and a temporary discount of -20% in the UK), I've bought a set of injectors for my own M3! lol.
Will add them soon.
In part to this (and a temporary discount of -20% in the UK), I've bought a set of injectors for my own M3! lol.
I’m probably in the minority on this but I think ethanol in modern gas doesn’t play nicely at all with our stock spec injectors. Or perhaps something else in our fuel systems. Compound that with how these cars are treated sometimes; barely drive garage queens. This makes for a great recipe for bore scoring and hydrolock. Much like in Porsche engines of the same era.
spammysammich Interesting, re Porsche engines, that's been shown to be the case?***************************************
Recently found cases to be added to list :-
Chris Morris E9X M3 V8 FB group (6-2021) - https://www.facebook.com/groups/1281553018523429/permalink/4343475868997780/ injector failed (pulled injector apart and found no debris in the gauze), 83k miles, MY 2011, USA - case added
Johnny Johnny E9X M3 V8 FB group (2021) - no2 cyl scored, but apparently all injectors tested ok! He thought it was down to a failed throttle actuator (6-2021), but I really can't see that! Then in 2-2022 stated a jammed injector, 40k miles, MY 2010, USA - https://www.facebook.com/groups/1281553018523429/posts/4343475868997780/?comment_id=4344012715610762 - case added
Derin Berry E9X M3 V8 FB group (11-2021) - thought injector failure damaged piston (bore not seen), thought cyl 7, MY 2008, 122k miles, USA - https://www.facebook.com/groups/1281553018523429/posts/4873965792615449/?comment_id=4880732465272115 - case added
Nick Davis E9X M3 V8 FB group - injector, MY 2011 (8-2021), 62k miles, USA - https://www.facebook.com/groups/1281553018523429/posts/4873965792615449?comment_id=4880732465272115&reply_comment_id=4886626571349371 PM'd 4-2-26 - case added
RocketyMan's friend, injector jammed open which 'took out' his engine. Awaiting more details - https://www.m3post.com/forums/showpost.php?p=32605269&postcount=103
Cases from the UK still to be added [update] Now added 3 injector failed cases and a rod bearing failure caused by the VANOS cover breaking up and blocking the oil pick up.
More to follow!
Another 4 cases added of injector failures taking out engines!
And created a new list where injectors failed but apparently didn't damage their engine, 4 lucky boys there! (although I do wonder what their compressions would be like!).
Now that I'm word searching within FB groups, I'm unearthing a lot of old cases!
And created a new list where injectors failed but apparently didn't damage their engine, 4 lucky boys there! (although I do wonder what their compressions would be like!).
Now that I'm word searching within FB groups, I'm unearthing a lot of old cases!
